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  <title>The SplDoublyLinkedList class</title>
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 <h1 class="title">The SplDoublyLinkedList class</h1>
 
 
 <div class="partintro"><p class="verinfo">(PHP 5 &gt;= 5.3.0, PHP 7, PHP 8)</p>
 

  <div class="section" id="spldoublylinkedlist.intro">
   <h2 class="title">简介</h2>
   <p class="para">
    The SplDoublyLinkedList class provides the main functionalities of a doubly linked list.
   </p>
  </div>

 
  <div class="section" id="spldoublylinkedlist.synopsis">
   <h2 class="title">类摘要</h2>
 

   <div class="classsynopsis">
    <div class="ooclass">
     
    </div>

    <div class="classsynopsisinfo">
     <span class="ooclass">
      <span class="modifier">class</span> <strong class="classname">SplDoublyLinkedList</strong>
     </span>

     <span class="oointerface"><span class="modifier">implements</span> 
       <a href="class.iterator.html" class="interfacename">Iterator</a></span><span class="oointerface">,  <a href="class.countable.html" class="interfacename">Countable</a></span><span class="oointerface">,  <a href="class.arrayaccess.html" class="interfacename">ArrayAccess</a></span><span class="oointerface">,  <a href="class.serializable.html" class="interfacename">Serializable</a></span> {</div>

    <div class="classsynopsisinfo classsynopsisinfo_comment">/* 常量 */</div>
    <div class="fieldsynopsis">
     <span class="modifier">public</span>
     <span class="modifier">const</span>
     <span class="type">int</span>
      <var class="fieldsynopsis_varname"><a href="class.spldoublylinkedlist.html#spldoublylinkedlist.constants.it-mode-lifo"><var class="varname">IT_MODE_LIFO</var></a></var>;</div>

    <div class="fieldsynopsis"><span class="modifier">public</span>
     <span class="modifier">const</span>
     <span class="type">int</span>
      <var class="fieldsynopsis_varname"><a href="class.spldoublylinkedlist.html#spldoublylinkedlist.constants.it-mode-fifo"><var class="varname">IT_MODE_FIFO</var></a></var>;</div>

    <div class="fieldsynopsis"><span class="modifier">public</span>
     <span class="modifier">const</span>
     <span class="type">int</span>
      <var class="fieldsynopsis_varname"><a href="class.spldoublylinkedlist.html#spldoublylinkedlist.constants.it-mode-delete"><var class="varname">IT_MODE_DELETE</var></a></var>;</div>

    <div class="fieldsynopsis"><span class="modifier">public</span>
     <span class="modifier">const</span>
     <span class="type">int</span>
      <var class="fieldsynopsis_varname"><a href="class.spldoublylinkedlist.html#spldoublylinkedlist.constants.it-mode-keep"><var class="varname">IT_MODE_KEEP</var></a></var>;</div>


    <div class="classsynopsisinfo classsynopsisinfo_comment">/* 方法 */</div>
    <div class="methodsynopsis dc-description">
   <span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.add.html" class="methodname">add</a></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$index</code></span>, <span class="methodparam"><span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.bottom.html" class="methodname">bottom</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.count.html" class="methodname">count</a></span>(): <span class="type">int</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.current.html" class="methodname">current</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.getiteratormode.html" class="methodname">getIteratorMode</a></span>(): <span class="type">int</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.isempty.html" class="methodname">isEmpty</a></span>(): <span class="type">bool</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.key.html" class="methodname">key</a></span>(): <span class="type">int</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.next.html" class="methodname">next</a></span>(): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.offsetexists.html" class="methodname">offsetExists</a></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$index</code></span>): <span class="type">bool</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.offsetget.html" class="methodname">offsetGet</a></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$index</code></span>): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.offsetset.html" class="methodname">offsetSet</a></span>(<span class="methodparam"><span class="type">?</span><span class="type"><span class="type">int</span><span class="type"></span></span> <code class="parameter">$index</code></span>, <span class="methodparam"><span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.offsetunset.html" class="methodname">offsetUnset</a></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$index</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.pop.html" class="methodname">pop</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.prev.html" class="methodname">prev</a></span>(): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.push.html" class="methodname">push</a></span>(<span class="methodparam"><span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.rewind.html" class="methodname">rewind</a></span>(): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.serialize.html" class="methodname">serialize</a></span>(): <span class="type">string</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.setiteratormode.html" class="methodname">setIteratorMode</a></span>(<span class="methodparam"><span class="type">int</span> <code class="parameter">$mode</code></span>): <span class="type">int</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.shift.html" class="methodname">shift</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.top.html" class="methodname">top</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.unserialize.html" class="methodname">unserialize</a></span>(<span class="methodparam"><span class="type">string</span> <code class="parameter">$data</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.unshift.html" class="methodname">unshift</a></span>(<span class="methodparam"><span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>): <span class="type"><span class="type void">void</span></span></div>
<div class="methodsynopsis dc-description"><span class="modifier">public</span> <span class="methodname"><a href="spldoublylinkedlist.valid.html" class="methodname">valid</a></span>(): <span class="type">bool</span></div>

   }</div>
 
  </div>


  <div class="section" id="spldoublylinkedlist.constants">
   <h2 class="title">预定义常量</h2>
   <div class="section" id="spldoublylinkedlist.constants.iteration-direction">
    <h2 class="title">Iteration Direction</h2>
    <dl>

     
      <dt id="spldoublylinkedlist.constants.it-mode-lifo"><strong><code>SplDoublyLinkedList::IT_MODE_LIFO</code></strong></dt>

      <dd>

       <p class="para">
        The list will be iterated in a last in, first out order, like a stack.
       </p>
      </dd>

     

     
      <dt id="spldoublylinkedlist.constants.it-mode-fifo"><strong><code>SplDoublyLinkedList::IT_MODE_FIFO</code></strong></dt>

      <dd>

       <p class="para">
        The list will be iterated in a first in, first out order, like a queue.
       </p>
      </dd>

     

    </dl>

   </div>

   <div class="section" id="spldoublylinkedlist.constants.iteration-behavior">
    <h2 class="title">Iteration Behavior</h2>
    <dl>

     
      <dt id="spldoublylinkedlist.constants.it-mode-delete"><strong><code>SplDoublyLinkedList::IT_MODE_DELETE</code></strong></dt>

      <dd>

       <p class="para">
        Iteration will remove the iterated elements.
       </p>
      </dd>

     

     
      <dt id="spldoublylinkedlist.constants.it-mode-keep"><strong><code>SplDoublyLinkedList::IT_MODE_KEEP</code></strong></dt>

      <dd>

       <p class="para">
        Iteration will not remove the iterated elements.
       </p>
      </dd>

     

    </dl>

   </div>
  </div>



 
 </div>
 
 

























































































 







































 
<h2>目录</h2><ul class="chunklist chunklist_reference"><li><a href="spldoublylinkedlist.add.html">SplDoublyLinkedList::add</a> — Add/insert a new value at the specified index</li><li><a href="spldoublylinkedlist.bottom.html">SplDoublyLinkedList::bottom</a> — Peeks at the node from the beginning of the doubly linked list</li><li><a href="spldoublylinkedlist.count.html">SplDoublyLinkedList::count</a> — Counts the number of elements in the doubly linked list</li><li><a href="spldoublylinkedlist.current.html">SplDoublyLinkedList::current</a> — Return current array entry</li><li><a href="spldoublylinkedlist.getiteratormode.html">SplDoublyLinkedList::getIteratorMode</a> — Returns the mode of iteration</li><li><a href="spldoublylinkedlist.isempty.html">SplDoublyLinkedList::isEmpty</a> — Checks whether the doubly linked list is empty</li><li><a href="spldoublylinkedlist.key.html">SplDoublyLinkedList::key</a> — Return current node index</li><li><a href="spldoublylinkedlist.next.html">SplDoublyLinkedList::next</a> — Move to next entry</li><li><a href="spldoublylinkedlist.offsetexists.html">SplDoublyLinkedList::offsetExists</a> — Returns whether the requested $index exists</li><li><a href="spldoublylinkedlist.offsetget.html">SplDoublyLinkedList::offsetGet</a> — Returns the value at the specified $index</li><li><a href="spldoublylinkedlist.offsetset.html">SplDoublyLinkedList::offsetSet</a> — Sets the value at the specified $index to $value</li><li><a href="spldoublylinkedlist.offsetunset.html">SplDoublyLinkedList::offsetUnset</a> — Unsets the value at the specified $index</li><li><a href="spldoublylinkedlist.pop.html">SplDoublyLinkedList::pop</a> — Pops a node from the end of the doubly linked list</li><li><a href="spldoublylinkedlist.prev.html">SplDoublyLinkedList::prev</a> — Move to previous entry</li><li><a href="spldoublylinkedlist.push.html">SplDoublyLinkedList::push</a> — Pushes an element at the end of the doubly linked list</li><li><a href="spldoublylinkedlist.rewind.html">SplDoublyLinkedList::rewind</a> — Rewind iterator back to the start</li><li><a href="spldoublylinkedlist.serialize.html">SplDoublyLinkedList::serialize</a> — Serializes the storage</li><li><a href="spldoublylinkedlist.setiteratormode.html">SplDoublyLinkedList::setIteratorMode</a> — Sets the mode of iteration</li><li><a href="spldoublylinkedlist.shift.html">SplDoublyLinkedList::shift</a> — Shifts a node from the beginning of the doubly linked list</li><li><a href="spldoublylinkedlist.top.html">SplDoublyLinkedList::top</a> — Peeks at the node from the end of the doubly linked list</li><li><a href="spldoublylinkedlist.unserialize.html">SplDoublyLinkedList::unserialize</a> — Unserializes the storage</li><li><a href="spldoublylinkedlist.unshift.html">SplDoublyLinkedList::unshift</a> — Prepends the doubly linked list with an element</li><li><a href="spldoublylinkedlist.valid.html">SplDoublyLinkedList::valid</a> — Check whether the doubly linked list contains more nodes</li></ul>
</div>
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